Ootori Sakuya

Calls himself Chihaya's "older brother". While not related to her by blood, he takes care of various things in his stated role as butler. Taking the attitude of a serene older brother while facing Yoshino and the female students, for some reason he's coldhearted only to Kotarou. With unusual physical ability and knowledge, while having strange connections he puts on a display of calmly providing anything, as a flawless butler.

Spoiler

He is a former Rewrite user as same as Kotarou, who became into a familiar due to overuse of Rewrite ability. His surname is Ootori, because he has formed familiar-master contract with Chihaya, despite not being as a blood or even adoptive brother.